RAM 3500 2026 — technical service bulletin
Bulletin 21-005-26 · NHTSA communication 11027631 · issued Jan 8, 2026
Technical service bulletin
communication type
Power Train
component
2026
model years
1
vehicle entries
Official summary
Flash: Transmission Control Module (TCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0826-00 - Up/Down Shift Switch. ● P0827-00 - Up/down Shift Switch Circuit Low. ● P085F-00 - Up And Down Shift Switch Circuit Range/performance. Customers may also experience one or more of the following: ● **Customer is unable to switch the ignition to OFF when in Park gear. ● After shifting into Park, the Instrument Panel Cluster (IPC) will display that the transmission is in
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.